Equilibrium sampling through membranes of freely dissolved chlorophenols in water samples with hollow fiber supported liquid membrane
(2005) In Analytical Chemistry 77(15). p.4800-4809- Abstract
- The freely dissolved concentration (C-free) of pollutants is generally believed to be bioavailable and thus responsible for toxic effects. The C-free of organic weak acids and bases consists of a dissociated and a nondissociated fraction. By using chlorophenols as model compounds, a negligible-depletion extraction technique, equilibrium sampling through membranes (ESTM), was developed for the measurement of the nondissociated part of the C-free. Polypropylene hollow fiber membranes (280-mu m i.d., 50-mu m wall thickness, 0.1-mu m pore size, 15-cm length) were impregnated with undecane in the pores in the fiber wall as liquid membrane and filled with buffer solution in the lumen as acceptor. Then, the hollow fiber membranes were placed into... (More)
- The freely dissolved concentration (C-free) of pollutants is generally believed to be bioavailable and thus responsible for toxic effects. The C-free of organic weak acids and bases consists of a dissociated and a nondissociated fraction. By using chlorophenols as model compounds, a negligible-depletion extraction technique, equilibrium sampling through membranes (ESTM), was developed for the measurement of the nondissociated part of the C-free. Polypropylene hollow fiber membranes (280-mu m i.d., 50-mu m wall thickness, 0.1-mu m pore size, 15-cm length) were impregnated with undecane in the pores in the fiber wall as liquid membrane and filled with buffer solution in the lumen as acceptor. Then, the hollow fiber membranes were placed into the sample (donor) for an equilibrium extraction after sealing the two ends. The chlorophenol concentrations in the acceptor were then determined by direct injection into a HPLC system. Finally, the C-free Of the nondissociated and the dissociated species of a chlorophenol were calculated based on its measured concentration in the acceptor, its pK(a) value, and the measured pH in sample and acceptor. Theoretically calculated distribution coefficients (D = 8-970) agree well with the experimental enrichment factors (E-e(max) = 6-1124), and the equilibration time was observed to increase with increasing distribution coefficients (hours to days). The freely dissolved concentration of five chlorophenols, with a wide range of pKa (4.9-9.2) and log K-OW (2.35-5.24), were successfully determined in model solutions of humic acids and at low-ppb levels in river and leachate water. (Less)
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https://lup.lub.lu.se/record/150984
- author
- Liu, Jing-fu LU ; Jönsson, Jan Åke LU and Mayer, P
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Analytical Chemistry
- volume
- 77
- issue
- 15
- pages
- 4800 - 4809
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000230920600025
- scopus:23044449478
- pmid:16053291
- ISSN
- 1520-6882
- DOI
- 10.1021/ac0503512
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Analytical Chemistry (S/LTH) (011001004)
- id
- 6f56dced-c36f-42d4-a9e0-a676f3fb915e (old id 150984)
- date added to LUP
- 2016-04-01 12:37:23
- date last changed
- 2022-02-04 00:39:47
@article{6f56dced-c36f-42d4-a9e0-a676f3fb915e,
abstract = {{The freely dissolved concentration (C-free) of pollutants is generally believed to be bioavailable and thus responsible for toxic effects. The C-free of organic weak acids and bases consists of a dissociated and a nondissociated fraction. By using chlorophenols as model compounds, a negligible-depletion extraction technique, equilibrium sampling through membranes (ESTM), was developed for the measurement of the nondissociated part of the C-free. Polypropylene hollow fiber membranes (280-mu m i.d., 50-mu m wall thickness, 0.1-mu m pore size, 15-cm length) were impregnated with undecane in the pores in the fiber wall as liquid membrane and filled with buffer solution in the lumen as acceptor. Then, the hollow fiber membranes were placed into the sample (donor) for an equilibrium extraction after sealing the two ends. The chlorophenol concentrations in the acceptor were then determined by direct injection into a HPLC system. Finally, the C-free Of the nondissociated and the dissociated species of a chlorophenol were calculated based on its measured concentration in the acceptor, its pK(a) value, and the measured pH in sample and acceptor. Theoretically calculated distribution coefficients (D = 8-970) agree well with the experimental enrichment factors (E-e(max) = 6-1124), and the equilibration time was observed to increase with increasing distribution coefficients (hours to days). The freely dissolved concentration of five chlorophenols, with a wide range of pKa (4.9-9.2) and log K-OW (2.35-5.24), were successfully determined in model solutions of humic acids and at low-ppb levels in river and leachate water.}},
author = {{Liu, Jing-fu and Jönsson, Jan Åke and Mayer, P}},
issn = {{1520-6882}},
language = {{eng}},
number = {{15}},
pages = {{4800--4809}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Analytical Chemistry}},
title = {{Equilibrium sampling through membranes of freely dissolved chlorophenols in water samples with hollow fiber supported liquid membrane}},
url = {{http://dx.doi.org/10.1021/ac0503512}},
doi = {{10.1021/ac0503512}},
volume = {{77}},
year = {{2005}},
}